(Photographer unknown, 1954, http://www.idaillinois.org/cdm/ref/collection/p16614coll40/id/801, accessed 10/10/18)
Yes, it has been sixty-five years since this old, hot, and contentious debate was “settled” (at least in the minds of America’s Class 1 railroad officials) in favor of the diesel, but new factors have come into play over the years. In this paper, I will set out to prove that the steam locomotive, the king of the rails for a century and a quarter, deserves a second chance on the Class 1 railroads of the United States of America.
The Historical Background
To gain a true understanding of the nature of this debate, I must first provide you with the historical background of why the railroads switched from steam locomotion to diesel. Some of the things I will say apply to freight and passenger cars, too, but I will only consider locomotives for this paper.
In the United States, after the end of Word War II, the railroads were in bad need of restructuring. This was because wartime traffic had kept the railroads extremely busy during World War II. To handle the excess traffic, the railroads needed a lot of equipment. The only problem was that for the duration of the war, the Federal Government had imposed restrictions on domestic use of steel so that the Allies could use this steel to build the ships, trucks, tanks, and guns needed to defeat the Axis powers. This meant that there was very little steel available for the railroads to use to build new equipment.
What did the railroads do? They kept their old equipment chugging on, and pulled even older items off the scrap tracks and put them back in service. Frequently, these engines were already 20-30 years old, sometimes much more. Rebuilding little, old locomotives into bigger, new ones was a way around Federal restrictions, the most famous example being the Reading’s rebuilding of I-10sa class 2-8-0 Consolidations into T-1 class 4-8-4 Northerns (Karl Zimmermann. “Ramblings on the Reading.” Trains Magazine, Fall 2018), but this was not done often.
So, when the war was over, the railroads were left with poorly-maintained track, and a large collection of worn-out antique steam locomotives. The railroads needed some new power, and soon. The railroads were left with two choices: they could buy a fleet of new, modern steam locomotives, or they could switch to a new kind of locomotive: the diesel.
The infrastructure for steam was already in place, and steam was the “tried-and-true” source of motive power on railroads. Steam locomotives had a high horsepower-to-weight ratio, and very powerful single units could be built. Fuel was also cheap, and most spare parts for steam locomotives were easy to make. Steamers were also much cheaper to buy than the new diesels, for an engine of similar horsepower. However, steam was rather inefficient at converting heat to power-at-rail, and steam locomotives spent a large percentage of time in the shops being repaired and maintained. Steam also required a crew of at least two to operate: an engineer and a fireman (http://trainweb.org/tusp/steam_diesel.html).
Diesels, on the other hand, were new and somewhat untested, although the 1939 EMD FT diesel demonstrator set #103 had proven quite successful, and was still in service on the Southern Railway. Diesels had a high up-front cost compared to a steam locomotive, and fuel was more expensive, but diesels spent more time pulling trains and less time in the shop, and only required one man to operate (labor union restrictions would prevent this benefit from materializing for another 30 years, though.) These cost savings would pay for the more expensive locomotives, and getting a loan to finance the diesels, using the locomotives themselves as collateral would be easy. Also, the fact that diesels spent less time in the shop meant that fewer diesels could replace more steamers. Mass-produced, standardized diesel parts made repairs a snap. Diesels also did not pound down on the rails, like steam engines did. Diesels, because of their short-wheelbase trucks, were also a lot less picky about the quality of their track compared to steamers. The lower horsepower of diesels could be compensated for by buying several diesels, and running them “MU’ed” (Multiple Unit control) with a single crew in the first unit. The public at large also liked the “modern” diesels far more than the “old” steamers (http://trainweb.org/tusp/steam_diesel.html). The diesels also had the advantage of being able to pull more than a steam engine, assuming the two were of similar weight and horsepower (Al Krug, edited by P. Connor. “Steam vs. Diesel.” Publication date unknown, accessed 9/28/18, http://www.railway-technical.com/trains/steam-vs-diesel.html).
Can you guess which route the railroads took? Yep, they scrambled to buy as many diesels as they could, and almost completely got rid of steam in the span of only fifteen years.
The Men who Advanced the Steam Locomotive After the Demise of American Steam
Even though the US and many other countries around the world were rapidly losing any sense of value in steam, a few men never lost hope that the steam engine would someday manage to better the diesel. The first of these was Andre’ Chapelon, who rebuilt a number of steam engines working for the Paris-Orleans Railway in France to be 12% efficient, double the 6-7% average of an American steam locomotive. Chapelon did this by increasing the boiler pressure, the steam temperature, the size of the steam circuit, and by adding a more efficient exhaust system.
The next, and arguably the most important of these men, was Livio Dante Porta, an Argentinian who burst onto the steam locomotive scene with his first design in 1949, the Argentina. Argentina was the most efficient steam locomotive of the late steam era, with a thermal efficiency more than double that of conventional American locomotives (John Rhodes, “Steam v Diesel.” Trains Magazine, March/April 2011). Porta became the designer of three systems to increase the efficiency of a steam locomotive: the GPCS (Gas Producing Combustion System) firebox, the Lempor exhaust system, and PT (Porta Water Treatment.)
Porta inspired several followers, including David Wardale, Phil Girdlestone, Shaun McMahon, Nigel Day, and Roger Waller. These men continue his legacy as the man who kept the fire of the steam locomotive going, no matter how few new ones were built, or how poorly the steamers were viewed by railroads.
Updates in Steam
Now that we have observed some of the works of Chapelon, Porta, and their students, let us turn our attention to the specific advances which these men made. I will try to keep things simple, but it is impossible to avoid all numbers and mathematics when working with the mechanics of engines, boilers, etc.
GPCS is a type of firebox designed by Livio Dante Porta in the 1960’s (Author and date unknown. “Time Line of Steam Development.” http://www.trainweb.org/tusp/back.html, accessed 10/10/18). GPCS operates on a very simple principle: fuel burns cleanest and most efficiently as a gas. Solid fuel lies in the bottom of a GPCS firebox, just as with a regular firebox. However, in a GPCS firebox, the fuel is sprayed with exhaust steam from underneath. The fuel reacts with this steam, as well as with the air around it, to become a gas. This gas rises and is burned in the upper part of the GPCS firebox. This is the most efficient way to burn solid fuel as has been discovered to date.
The exhaust system is at the heart of any steam locomotive, because the exhaust steam from the cylinders is used to force a draft, and direct the heat from the locomotive’s fire into the boiler, rather than backward into the area that is normally the cab. While many exhaust systems have been developed to date, the most efficient is the Lempor, designed by Porta in 1952 (L.D. Porta. “Theory of the Lempor Ejector.” http://www.trainweb.org/tusp/lempor/lempor_theory.html, accessed 10/10/18). Work continues on an even more efficient successor to the Lempor system, called the Lemprex.
Porta Water Treatment is a chemical treatment of boiler water, designed to perform several functions. These include preventing scale from developing on the boiler walls, and prevention of foaming, which have the benefit of increased efficiency, dramatically reduced maintenance, and pure steam.
Higher Steam Pressure
The practice of increasing steam pressure has a simple rationale behind it: if you increase the pressure of the steam going to the cylinders, then the locomotive will be able to provide more power for the same amount of fuel, thus increasing efficiency. American locomotives at the end of steam had steam pressures of around 200 to 250 psi. Later “modern steam” designs in other countries had steam pressures of around 290 psi, and likely more would be desirable.
Higher Steam Temperature
Pressure and temperature are linked to each other. We call this the “Ideal Gas Law.” According to the Ideal Gas Law, if you keep a gas at a set volume (i.e. in a container,) and increase the temperature, the pressure will rise, and vice versa. So, applied to a steam locomotive, if you increase steam temperature, you will also increase the pressure, which, as we have seen, increases efficiency. Raising the steam temperature also has the added benefit of evaporating any remaining water droplets still suspended in the steam, and this increases the pressure even more.
When you look at the advances that I have shown, you can see how significant they are. However, is it enough to overcome the diesel? Let’s take a more detailed look.
Before we begin, though, I have to note that all calculations are theoretical only. No steam locomotive has ever been built that incorporates all of the features to make a steam locomotive as efficient as it can possibly be. Any steam locomotive that could be considered “modern” only incorporates some of the improvements that I have mentioned, not all of them. This is the single largest limiting factor that explains why steam has still not made a comeback on the railroads of the US. But, with computer software that is used by the railroads to calculate locomotive performance, we can still get a very good simulation of how a modern steam locomotive would perform.
For a modern steam locomotive to even get a chance at being accepted by the Class 1s, it must be able to equal the performance of a modern diesel locomotive. The best comparison I have found is a portion of an article by John Rhodes on the subject.
“A modern steam locomotive for US Class 1 railroads should be comparable in performance to a General Electric (GE) ES44AC. This is a very typical locomotive in Class 1 service today. The ES44AC has a 4,400 hp prime mover, six powered axles, 180,000 pounds starting tractive effort SLS Journal 61 and dynamic brakes. A Third Generation [sic] steam locomotive in the form of a five cylinder, 2-8-8-2 could match the performance of an ES44AC. The steam locomotive would have a diesel type cab in the end of the tender, along with compression braking in lieu of dynamic brakes. The steam locomotive would utilize triple expansion, having one high pressure and one intermediate pressure cylinder on one engine group and three low-pressure cylinders on the other engine group. The principal specifications of this locomotive are as follows:
Thermal efficiency 21 percent At [sic] drawbar
Maximum HP 5,900 At [sic] drawbar
Maximum tractive effort 180,000 Pounds
Driver diameter 60 Inches
Full weight 1,500,000 Pounds
Max speed 90 MPH
Grate area 71 Square feet
Average hourly coal 2.44 Tons
Average hourly water 2,880 Gallons
Tender: 4 axles
Coal capacity 51 Tons
Water capacity 10,474 Gallons
2 water tank cars 50,000 Gallons total
Running time 21 Hours
The 2-8-8-2 is approximately 118 feet for the engine and tender and another 120 feet for both water tank cars. The locomotive is 15.5 feet tall…
…All 2-8-8-2 performance data is estimated from the Porta proposed Third Generation 2-10-0
of 1978 with the assistance and concurrence of Shaun McMahon and Nigel Day.
In the past, it has been said that the cost of fuel for steam locomotives sitting at idle was high.
Today this wouldn’t be the case, due to better design and low fuel cost. The 2-8-8-2 described above would cost 10% of the cost of an Auxiliary Power Unit (APU) equipped diesel locomotive sitting at idle. Also, the 2-8-8-2 would have a fuel and water range 6% greater than the ES44AC, due to its low fuel consumption and large tenders.” (John Rhodes, “Steam v Diesel.” Trains Magazine, March/April 2011)
Earlier in his article, Rhodes also addresses a very important point: we cannot one-up the diesel by simply modernizing an old-fashioned steam locomotive. To rival the diesel, any modern steamer must have all the comforts of a modern diesel, which is pretty much giving the crew their own apartment on rails. Also, a substitute for dynamic braking, called “compression braking,” would need to be used as well as some means to M.U. (Multiple Unit) locomotives, and electronic boiler controls would be a necessity to eliminate the position of fireman, a position gone from the Class 1s since the 1980s. Modern technology would make all this quite feasible, but such modern computer equipment would drive the cost of each locomotive up.
However, if we compare Rhodes’ calculations for cost of new locomotives, installation of refueling facilities, etc., then a conversion of the American class 1 railroads from diesel to steam would pay for itself in only a few years, because fuel cost savings alone would produce $50 billion in savings in the span of only 15 years, and this saving is with a $20 billion conversion cost subtracted out (John Rhodes, “Steam v Diesel.” Trains Magazine, March/April 2011).
And what about that easier maintenance that was the chief advantage of the diesels back in the early postwar era? Well, a study was done in South Africa, and a modern class of steam locomotive was found to require 20% less maintenance than a comparable diesel. An earlier study done in the US came to a similar conclusion (John Rhodes, “Steam v Diesel.” Trains Magazine, March/April 2011).
So, it looks like the railroads may want to try to return to
steam. The railroads will probably
object about compatibility with diesels, their current investment in diesel,
etc. I think that the economic gains
should override these concerns, but each railroad must leave the decision up to its management. Other experimental engine types also vie for the railroads’ time, and the relative lack of mainline success for these types seem to have the railroads soured about building or buying risky new experimental locomotives for the decade of the 2010s. It may well be a private company, sometime in the future, perhaps the 2020s or 2030s, that builds a demonstrator to prove the viability of steam. This has been tried, and the closest attempt to success was the ACE 3000 project in the 1980s, but for success, heavy financial backing will be needed, which was the downfall of the ACE 3000 (Author unknown. “ACE 3000.” publication date unknown, https://www.american-rails.com/ace-3000.html, accessed 10/10/18).
If the modern steam locomotive were to enter regular US service, the economic impact has the potential to be enormous. The reduced demand for refined oil, presuming that the new steamers would be burning coal, wood, or some other fuel, would drive oil prices down, and so make it cheaper to pay for gas in your own car. Several options for fuel are also available in the form of “waste,” such as excess wood chips from tree farms or sawmills. These “fuels” may prove most economical for short-range operation of a modernized “fireless” steam locomotive (Harry Valentine. “Researching the Ultimate Fireless Steam Locomotive.” 3 Parts. Publication date unknown, http://www.martynbane.co.uk/modernsteam/hvalentine/fireless1.htm, http://www.martynbane.co.uk/modernsteam/hvalentine/fireless2.htm, http://www.martynbane.co.uk/modernsteam/hvalentine/fireless3.htm, accessed 10/10/18).
In this ever-environmentally conscious age, the use of “alternative” fuels would be good for railroad public relations for sure. Even then, some railroads may not be convinced. But then we at least can say that the steamer had a fair head-to-head competition with the diesel. And what if a person on some railroad’s board of directors likes the steamer? Then we may have just changed the course of history in ways we may never fully measure.
What are your thoughts?
Author unknown. “ACE 3000.” https://www.american-rails.com/ace-3000.html, accessed 10/10/18.
Author and date unknown. “Time Line of Steam Development.” http://www.trainweb.org/tusp/back.html, accessed 10/10/18.
Author and date unknown. Diesel-electric vs. Steam Locomotives, http://trainweb.org/tusp/steam_diesel.html, accessed 10/10/18.
Photographer unknown, 1954, http://www.idaillinois.org/cdm/ref/collection/p16614coll40/id/801, accessed 10/10/18.
Al Krug, edited by P. Connor. “Steam vs. Diesel.” Publication date unknown, http://www.railway-technical.com/trains/steam-vs-diesel.html, accessed 9/28/18.
L.D. Porta. “Theory of the Lempor Ejector.” http://www.trainweb.org/tusp/lempor/lempor_theory.html, accessed 10/10/18.
John Rhodes. “Steam vs Diesel: A Comparison of Modern Steam and Diesel in the Class 1 Environment.” Trains Magazine, Mar./Apr., 2011, pgs. 54-66, http://www.stephensonloco.org.uk/journal%20content/WJ868%20Steam%20v%20Diesel%20%20John%20Rhodes%2054-66.pdf, accessed 9/28/18.
Harry Valentine. “Researching the Ultimate Fireless Steam Locomotive.” 3 Parts. Publication date unknown, http://www.martynbane.co.uk/modernsteam/hvalentine/fireless1.htm, http://www.martynbane.co.uk/modernsteam/hvalentine/fireless2.htm, http://www.martynbane.co.uk/modernsteam/hvalentine/fireless3.htm, accessed 10/10/18).
Karl Zimmermann. “Ramblings on the Reading.” Classic Trains, Fall 2018, pg. 22.